fix extern c location

src/core/lib/surface/completion_queue.h

@@ -49,6 +49,10 @@ extern grpc_tracer_flag grpc_trace_operation_failures;
 extern grpc_tracer_flag grpc_trace_pending_tags;
 #endif
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 typedef struct grpc_cq_completion {
   gpr_mpscq_node node;
 
@@ -108,4 +112,8 @@ int grpc_get_cq_poll_num(grpc_completion_queue *cc);
 grpc_completion_queue *grpc_completion_queue_create_internal(
     grpc_cq_completion_type completion_type, grpc_cq_polling_type polling_type);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* GRPC_CORE_LIB_SURFACE_COMPLETION_QUEUE_H */

test/cpp/qps/client.h

@@ -46,6 +46,7 @@
 #include <grpc/support/log.h>
 #include <grpc/support/time.h>
 
+#include "src/core/lib/surface/completion_queue.h"
 #include "src/proto/grpc/testing/payloads.pb.h"
 #include "src/proto/grpc/testing/services.grpc.pb.h"
 
@@ -54,10 +55,6 @@
 #include "test/cpp/qps/usage_timer.h"
 #include "test/cpp/util/create_test_channel.h"
 
-extern "C" {
-#include "src/core/lib/surface/completion_queue.h"
-}
-
 namespace grpc {
 namespace testing {
 

test/cpp/qps/server.h

@@ -38,16 +38,13 @@
 #include <grpc/support/cpu.h>
 #include <vector>
 
+#include "src/core/lib/surface/completion_queue.h"
 #include "src/proto/grpc/testing/control.pb.h"
 #include "src/proto/grpc/testing/messages.pb.h"
 #include "test/core/end2end/data/ssl_test_data.h"
 #include "test/core/util/port.h"
 #include "test/cpp/qps/usage_timer.h"
 
-extern "C" {
-#include "src/core/lib/surface/completion_queue.h"
-}
-
 namespace grpc {
 namespace testing {